ABSTRACT
AIMS AND PURPOSE: To identify patterns and rates of adherence with travoprost eye drops using the Travatan dosing aid (TDA) and to present a method for graphically presenting adherence data. METHODS: A prospective observational cohort study of patients on travoprost (prostaglandin) monotherapy. Patients were dispensed a TDA and followed up after approximately 3 months of usage. Data were downloaded from the TDA into a computer for analysis. Analysis used inter-dose intervals (the time between each dosing) to look at adherence between days 4 and 75. RESULTS: In all, 100 patients were invited to participate, 53 agreed and complete TDA data sets were obtained from 37. In total 23 of the complete data sets showed good adherence (dosing within +/-4 h of the agreed dosing time on >80% of occasions), 3 patients discontinued usage before 75 days, 4 showed frequent drug holidays (no dosing for > or =8 days) and 7 frequently missed doses with adherence rates of <60%. Of the 16 patients for whom no TDA data was obtained, 5 were lost to follow-up, 4 had faulty/damaged TDAs, 3 changed medication, 3 preferred not to use the TDA, and 1 was hospitalized. CONCLUSIONS: There were four easily defined patterns of adherence; (1) good adherence; (2) discontinued usage; (3) frequent drug holidays; and (4) frequent missed doses with low adherence rates. A new method for graphically presenting adherence data helps clinicians identify the pattern of usage and is a valuable aid to the overall management of patients on travoprost therapy.
